Patent · US Expired

Apparatus for detecting faults in transparent objects

US4547067A · kind A · utility

19Cited by
5References
13Claims
0Family size

Assignee

Inventor

Key dates

Filing dateDec 13, 1983
Grant dateOct 15, 1985
Priority date
Expiry dateDec 13, 2003

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01N21/9018
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

In a detecting system adapted to detect foreign matters as faults of a glass bottle, between a projection path of a diffused light towards the object to be inspected and said object, a plane polarizing plate of a circular polarizer which includes the plane polarizing plate combined with a 1/4 wave plate is disposed at the side of a diffused light side, while, in a light path which causes light transmitted through the object to form an image on the photoelectric detector 6 through the lens, a detecting side circular polarizer which includes a 1/4 wave plate and a plane polarizing plate is placed. An output electric signal of the photoelectric detector is subjected to analog operation processing.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.